Усилители мощности моно — Mark Levinson ML-50

The ML-50 is a limited-edition monaural power amplifier that Mark Levinson announced on 4 January 2022 to mark the company's 50th year. Production was capped at 100 serialised pairs, sold as a system at USD 50,000 per pair with deliveries from the fourth quarter of 2022. The name recalls the ML-2 of 1977 to 1986, and design, engineering and final assembly all take place in the USA, as the maker states.

Key specs that matter

Each chassis is rated at 425 W RMS into 8 ohms and 850 W RMS into 4 ohms from 20 Hz to 20 kHz, and it is stable down to 2 ohms. The first 20 W into 8 ohms are delivered in Class A. Voltage gain is 26 dB, so 142 mV at the input gives 2.83 V at the output. THD is under 0.04% at 1 kHz and full power and under 0.3% across the audio band, noise sits more than 85 dB below the 2.83 V reference, and response runs from 10 Hz to 20 kHz within +0/-0.2 dB. Input impedance is 60 kohm on XLR and 30 kohm on RCA. The unit is 197 mm tall, 438 mm wide and 533 mm deep and weighs 52.2 kg. It draws 560 W at idle against a 1,500 W mains rating, with standby modes of 65 W, 5 W and under 0.5 W.

Engineering and use context

The audio circuit comes from the № 536 and follows the Pure Path topology, but the Class A output was quadrupled compared with that platform. Capacitance in the high-voltage supply rose by 50% to lower the noise floor, and the main high-current supply gained 20%. The styling quotes three earlier models - large front handles from the № 20 family, outrigger feet from the № 33, a glass front and red backlit logo from the № 53. A clear glass lid exposes the interior, which can be lit red or white or left dark, and heat leaves through external heat sinks and twin vents in the top panel. The feet are mechanically isolated to damp vibration. Bi-wiring is possible through two sets of Hurricane speaker terminals, and Ethernet, RS-232, 12 V trigger connections, micro USB and USB-A cover control and service. Each package ships as three cartons stacked on a wooden pallet, containing the two amplifiers, two 3 m power cords, white gloves and a polishing cloth.

Pairing

The balanced input suits a preamplifier fitted with XLR sockets, and a trigger cable lets the pair switch on with it. The low-impedance stability and the power doubling as impedance halves make low-impedance floorstanding loudspeakers a suitable load.

Alternatives

The Mark Levinson № 631 is a later mono amplifier from the 600 Series, housed in a tall chassis designed to stand on the floor.